How to set system images (path?) when creating an Android AVD?

Pay attention that android is deprecated. Use avdmanager.

First, you need to download the necessary packages.
Example of downloading API 23 packages for x86 emulators:

 ./sdkmanager "system-images;android-23;google_apis;x86"

Then accept the license agreement

 ./sdkmanager --licenses

and then create your emulator

./avdmanager create avd -n test -k "system-images;android-23;google_apis;x86" -b x86 -c 100M -d 7 -f